# Quantum Cryptography II: How to re-use a one-time pad safely even if P=NP

@article{Bennett2014QuantumCI, title={Quantum Cryptography II: How to re-use a one-time pad safely even if P=NP}, author={Charles H. Bennett and Gilles Brassard and Seth Breidbart}, journal={Natural Computing}, year={2014}, volume={13}, pages={453 - 458} }

When elementary quantum systems, such as polarized photons, are used to transmit digital information, the uncertainty principle gives rise to novel cryptographic phenomena unachievable with traditional transmission media, e.g. a communications channel on which it is impossible in principle to eavesdrop without a high probability of being detected. With such a channel, a one-time pad can safely be reused many times as long as no eavesdrop is detected, and, planning ahead, part of the capacity of…

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